In various conventional network communication systems, a user equipment will perform a cell re-selection procedure when the user equipment determines that the communication condition between the user equipment and a base station originally connected to the user equipment is poor so as to attempt to establish connection with other base stations satisfying connection quality requirements, thereby maintaining good service quality. Similarly, the NB-IoT network communication system has the corresponding cell re-selection procedure.
In detail, the cell re-selection procedure used by the NB-IoT network communication system currently available still mainly use the conventional cell re-selection processes and determines whether to perform base-station re-selection by a single re-selection judgment formula. Therefore, cell re-selection is performed as long as requirements of the re-selection judgment formula are satisfied regardless of the nature or status of the user equipment.
However, due to relatively high consistency of the nature of the user equipments in the conventional network communication system, the single re-selection judgment formula can satisfy requirements of most of the user equipments for cell re-selection. But in the NB-IoT network communication system, usually there are user equipments of which the nature is different from others to a large extent. Accordingly, if the single re-selection judgment formula is used as the criterion of determining whether to perform cell re-selection for all the user equipments in the NB-IoT network communication system, the utilization efficiency of network resources will be poor in the cell re-selection for part of the user equipments, thereby remarkably reducing the reliability of the overall network.
Accordingly, an urgent need exists in the art to perform appropriate cell re-selection procedures for user equipments of different natures in the NB-IoT network communication system, thereby improving the utilization efficiency of the network resources and meanwhile increasing the reliability of the network.